Solenoid and armature formed of strip material



Y 2,467,489 SOLENOID AND ARMATURE FORMED 0F STRIP MATERIAL Filed nec. 19, 1946 y Sheets-Sheet 1 J. w. MccLAIN VQ' at Aprill 19, 1949.

April 19, 1949. J. w. MccLAlN 2,467,489

SQLENOIDVAND ARMATURE FORMED OF STYRIP MATERIAL Filed Dec. 19, 194e 2 sheets-sheet 2 Patented Apr. 19, 19491 SOLENOID AND ARMATURE FORMED F r STRIP MATERIAL Joseph W. McClain, Lonnsport, Ind., assigner to Essex Wire Corporation, Logansport, Ind., a corporation of Michigan Application December 19, 1946 Serial No. 717,249

4 Claims. (Cl. 175-338) My invention relates to an improved form of solenoid -for general usage.

One type of solenoid presently on the market has a frame for the energizing coil and an armature actu-ated by Ithe energizing coil, both formed of laminations of magnetic material stacked side to side and then riveted together. In my improved form of solenoid which I shall describe yat greater length hereinafter I provide an armature and a frame for fthe energizing coil each formed of a single continuous strip of magnetic material which is wound upon itself. Such form of construction is much less expensive since it avoids handling of the many lamlnations and numerous rivets and also avoids several riveting operations.

Another 4difficulty in the laminated cons-truction currently in use is that the rivets in the magnetic structure cause a large portion of the losses incurred in oper-ation of the solenoid. Tests of my new form of solenoid have shown approximately a 25% increase in eiiiciency over the laminated structures heretofore employed.

Starting with a stamped blank of magnetic strip material having two portions of diierent widths, I am able to form the supporting member for the energizing coil with a closed end wall and with ra similar blank can form the arm-ature with a head of larger dia-meter than its shaft portion. Ifit is found desirable it is possible to employ the same blanks for both the vframe member and :the armature, it only being necessary to wind the blanks upon themselves from opposite ends, namely, in Ithe case of the frame member, from the end having the narrower width and, in the case of the armature, from the end having the wider width.

In addition to lower cost of manufacture and greater eiciency other advantages', and uses ol' my invention will become apparent from the following description when taken with the drawings in which:

Figure l is :an elevation-al view of the solenoid with the armature in retracted position;

Figure 2 is an enlarged end view of the solenoid looking in the direction of the arrows 2-2 of Figure 1; v

Figure 3 is an enlarged end view of the armature of Figure 1 looking inthe direction of the arrows 3-3 of Figure 1;

Figure 4 is an enlarged sectional view on line 4-4 of Figure 1;

Figure 5 is an enlarged sectional-view on the line 5-5 of Figure 1;

Figure 6 is an enlarged sectional view taken on the line B-B of Figure 5 Figure 7 is an enlarged elevational view of the armature with portions broken away;

Fig-ure 8 is an enlarged sectional View on the line 8-8 of Figure 7; and

Figure 9 is a pl-an view on reduced scale of a blank such yas that employed in forming the armature of Figure 7.

Like reference numerals have been employed in lthe several views to indicate the same or similar elements.

Referring now -particularly to Figures 1 through 5 a solenoid is indicated generally by the reference numeral I 0 and consists principally of an armature l2, an energizing coil I4, `a supporting frame IB for the energizing coil and a support bracket i8 having a ange 20.

Both the armature l2 and the frame member I6 are formed of a single blank of magnetic strip material. Such blank may take the form indicated in Figure 9 although lthe exact dimensions of said blank may vary depending upon the size of the device and whether the blank is to be used for the armature or for the frame. However it is possible to employ the same sized blank for both members, if that is desired. In Figure 9 the blank, indicated generally by the reference numeral 22, consists of a narrow portion 24 anda wider portion 2-6 which may be formed integrally width portion 24 or may be formed separately and welded to portion 24 as indicated at 28. The portions 24 and 26 provide ya common edge 30 along their one sides.

When the blank is to be employed for constructing an arma-ture, -a small notch 32 Will be formed on the wider portion 26 on that edge which is opposite the common edge 30. Then when blank 22 is wound upon itself the notch 32 will leave an annular space in which a shading coil may be positioned. When the blank 22 is to be employed to form the fra-me member I6 thenotch 32 is omitted. When the same blank 22 is to be employed for forming both the armature and the frame member |15 the notch 32 may be employed in all blanks and its presence ignored when the blank is used to form a frame member. In forming a frame member I6 from la blank, such as blank 22, the blank is Wound upon itself beginning yat the free end of the narrower accuse porting bracket I8 by a single pin or rivet 84 which passes through holes formed in the bracket I8 and in the coiled end wall 36 of the frame member I6. Preferably pin, 34 extends diametrically through the end Wall 36.

The magnetic coil assembly I4 is positioned within the frame member I6 and is retained therein by a retainer ring 38 adjacent the open end of member I6. The arms 40 of ring 38 pass through apertures 4'I in the frame member I6 and apertures 42 in the bracket I8. TheV ring 88 is split and its free ends may be directed toward each other by employing apair of long nose pliers inserted in the holes 44'of said ring in order to radially retract the arms 40 so that said ring may have the arms inserted in the passageways 4I and 42 after the coil assembly I4 is positioned in frame I6.

The coil assembly I4 comprises a brass sleeve 4'5 around which is concentrically placed an insulating sleeve 46 on which the coil of wire 48 is wound to form an electromagnet. At either end of coil 48 are positioned insulating washers 50 and 52 which are retained in position by anges 54 and 56 on the brass sleeve 45. Preferably the exterior surface of the coil of wire 48 is covered with insulation to prevent short circuiting with the frame member I6. The leads l of the coil 48 extend out of the frame member I6 through its apertures 4I and through the apertures 42 of the bracket I8.

Considering now the armature I2 and referring more particularly to Figures 5 through 8 it will be seen that winding a blank, such as blank 22 of Figure 9, from the larger end 26 will form `a shaft 6I) of one diameter and a head 58 of a larger diameter from the single blank of material. The mechanism (not shown) which is to be operatedby the armature I2 is connected with the ears 62 of the cap member 64 which is connected to the head 58 of armature I2 by a single diametrically extending pin 66. Pin 66 secures the coils of head 58 together and secures the lugs 68 of the cap member 64 to the head 58 of armature I2. At the free end of the shaft 60 there will be seen internally positioned a shading coil 'I0 which occupies the angular space formed by the notch 32 (see Figure 9) when the blank 22 is wound upon itself. The diameter of shaft 60 is smaller than the diameter of head 58 and is adapted to move within the sleeve 45 of the coil assembly I4. The end of shaft 60 when it strikes the end Wall 36 forms a stop for the armature when it is drawn upwardly by the magnetic coil assembly I4.

{Although I have illustrated a preferred form of my invention it will be apparent that certain changes and modifications may be made therein without departing from the scope of the invention as dened in the appended claims.

I claim: i

1. An armature adapted to be used in a. solenoid, said armature having a shaft portion of one diameter and a head of a larger diameter, an annular space at the free end of the shaft portion, and a shading coil iixed in said annular space, said armature being formed of magnetic strip metal spirally wound upon itself from its ferent widths with a common edge and a notch wider portion, said strip having portions of difin the wider portion at the edge opposite said common edge.

2. In a solenoid, an energizing coil, an armature actuated by said coil, and a supporting frame for said coil, said armature having a cylindrical shaft and a head formed of spirally wound magnetic material, and said frame having a closed end and being formed of spirally wound magnetic material, a supporting bracket, a pin passing diametrically through the closed end of the frame and through the bracket to'secure the frame against unwinding and to secure the bracket to the frame, a cap, and a pin passing diametrically through the head of the armature and through the cap to secure the armature against unwindmg and to secure the cap to the armature.

3. In a solenoid, an energizing coil, an armature actuated by said coil, and supporting frame for said coil, said armature having a cylindrical shaft and a head formed of spirally wound magnetic material, and said frame having a closed end and being formed of spirally wound magnetic material, a supporting bracket, a pin passing diametrically through the closed end of the frame and through the bracket to secure the frame against unwinding and to secure the bracket to the frame, a cap, a pin passing diametrically through the head of the armature and through the cap to secure the armature against unwinding and to secure the cap to the armature, an annular space at the free end of the shaft portion, and a shading coil disposed in said annular space, the strip from which the armature is Wound having portions of different widths with a common edge and a notch in the Wider portion at the edge opposite said common edge.

4. A blank for forming an armature having a shaft, an enlarged headl and a recess for receiving and retaining an annular shading ring in the shaft, said blank comprising a generally longitudinally extending piece of strip metal having two portions of diierent widths joined together lengthwise, the narrower portion being joined to the wider portion adjacent one side edge of the latter, and a generally rectangular notch in the other side edge of the wider portion, the length of said notch being such that, when the blank is wound upon itself lengthwise to form the armature, an annular recess extending inwardly of the free end of the shaft is formed by the notch.

JOSEPH W. MCCLAIN.

REFERENCES GITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 352,202 Evans Aug. 25 1885 1,601,014 Wismer et al. Sept. 28, 1926 1,720,943 Chapman July 16, 1929 1,819,843 Richmond Aug. 18, 1931 2,222,419 McCarty Nov. 19,1940 2,310,684 Farry Feb. 9, 1943 

